Yeast culture in bread making and yeast propagation



Patented Feb. 21, 1939 ms'r cum-liar:

INBREADMAKING'AND YEAST PROPAGATION Roger J. Williams; Standard ds Corvallis, OR!

asaig'nor to Bran Incorporated, New York, N. Y., a corporation of Delaware No Drawing. Application hiereh 20, 10st,

Serial-No. 71,011 1:; Claims. (01. 90-

This invention to the culturing or yeast and has for its object the provision of specific nutrients and methods ior stimulating yeast srowth. f

Yeasts are produced commercially by growth of cultures or the desired types in media which provide the necessary food materials to nourish the growing plants. Among the media. used are solutions made from grain meshes, beet molasses, cane molasses and the like,- to which supple mental materials such as ammonia or ammo-' nium compounds, phosphates 'or other mineral substances have been added 'in certain cases. Synthetic media containing sugars and salts may 1 also, be employed for .yeast culture. After the yeast plants have grown and increased in amount and numbers, they are separated from the medium and further treated to produce either a wet or .a dry product, which may itself be used as a food ingredient, or for the production of fermentation products in other media, or for leavening as inbreadmaklng. In some'cases as in brewing, distilling, wine making, etc., the yeast crop itself may be without much value but its propagation in the medium is necessary for producing the desired amount of fermentation products.

I have discovered that the rate 01' growth of 30 yeast plants is greatly accelerated by the addition to the media of certain specific organic acids,

namely beta alanine, either separately or in combination with aspartic acid. Beta alanine or beta amino propionic acid though a relatively rare 35. chemical has been known for a number or years and has beam given the formula CsHqOsN. As-

partic acid or amino succinic acid has long been known same of the amino acids resulting from the decomposition of proteins and has-been given the lormula canons. Salts of these amino acids 7 or other derivatives which under the conditions existing "in the "culture medium would yield these acids are considered to be the equivalents of beta 6 alanine and aspar'tic' acid respectively. In experiments cited belowsynthetic' betaalanine I .and naturalaspartic acid (so-called i-aspartic acid) were used but these facts are cited as examplesand nottolimit theinvention to the parf 50 forms used. I have Ioundthatwhilebeta alanine gives accelerated yeast growth, nevertheless its use simultaneously with aspartic acid aivesinsomecasgsatieashsccelerationsgre'ater thancanbeattainedbybetaalaninealone. Dits ierent strains of yeastbebave somewhat differ! acid which are structurally related to beta "nine in that they have nitrogen attached onlyently to these substances as is indicated by the results given below. v

Furthermore I have found that other acids such as beta amino butyric acid and ,nicotinic alaon the beta position with respect to carbonyl, have the ability to affect yeast growth when used in low concentratio These particular acids are mentioned as exa ples, however, and not to m limit the invention to these specific acids, or to derivatives which yield them in the culture medium.

The effect-of adding one part of beta alanine hydrochloride alone to 12,000,000 parts by weight of culture medium was to increase the yeast crop 3.9 times in the case of "Gebruder Mayer-"yeast; 2.85 times in the case of W. Lash Miller's yeast;

4.1 times in the case of Rasse M" yeast (K081) and.1.12 times in the case of Wildiers' yeast.

The eflect of adding one part of aspartic acid (as the ammonium salt) to 16,000 parts by weight or culturemediumwastocausenoincreasein the case of Gebruder Mayer" yeast, an increase to 1.7 times the control in the-cased W. Lash Miller's yeast, a negligible increasein the case of Rasse M" yeast (Kogl) and an. increase to 1 1.6' times the control in the case of Wildiers yeast.

- When both beta alanine hydrochlorideand ammonium aspartate were added together in the proportions indicated above, the crop of Gebruder Mayer" yeast was 5.9 times that of the control, the cropof W. Lash Mlllersyeast was 1 0.3 times that of the control, the crop or Rise 11 yeast (Kogl) was 7.1 times that of the control, and the crop or Wildierslyeast was 4.4 times that oi the control culture.

In all of the above procedures medium contained the requisite sugar, inositol; ammonia, phom crus. l me. po s and ash slum compounds together with the trace ele- .ments thallium, manganese, boron; iron, copper I and iodine. Includedin the above medicare all the known chemicals which are required for yeast nutrition. The control-cultures and those towhlch additions were made were treated and seeded'enctlyalikeandtlseenvironmentaleonr ditionsduringgrowthwerethesameexoeptfor a thepresence or absenceofbetaalanineand/or aspartic-acidasindicated. -Whileintheeltedthesameproportionoibetaalaninewasusedthrwahoutand' acid was used, these amounts are not critical nor necessarily optimal. The optimum amounts to be used will depend, as will be understood by one skilled in the art, on the type of yeast, conditions of growth, kind of medium, etc. The examples are given for the purposes oi! illustration only and not as limitations of the invention. Likewise the particular yeasts are cited merely as examples and not as limitations of the invention. Likewise, while a synthetic medium made up from chemicals of ordinary purity, was used in the experiments cited, this is used for illustration and not to limit the invention to its use in connection with this particular type of medium.

All of the other'members of the amino acid group of compounds have nitrogen attached to the alpha position with respect to a carboxyl group, some have nitrogen attached tov the gamma, delta and epsilon positions but'not to the beta position. None of these when added to yeast cultures in like amounts causes stimulation. Compounds such as tartaric acid and malic acid which are structurally related to aspartic acid but contain no nitrogen also are without eflect even when used in relatively high doses. Asparagin which isthe acid amide o'f aspartic acid in some cases at least plays a role similar to that of aspartic acid itself, though it is not as eflective. Y

Additions of beta alanine and acids with related structure, or derivatives of these, separately or in combination with aspartic acid, may be used to accelerate-the growth or modify the quality of yeast in cultures, for the production a of the yeast itself, or they may be added to batches,

prises a yeast assimilable carbohydrate material,

a yeast nutrientinorganic salt and a monocarbonlic organic acid having nitrogen attached only to the beta position with respect to carboxyl.

2. A nutrient medium for yeaat which comprises a yeast assimilable carbohydrate material,

a yeast nutrient inorganic salt, andbeta alanine. 3. A nutrient medium for yeast which comprises'a. yeast assimilable carbohydrate material,

a yeast nutrient inorganic salt, beta alanine, and

. acid.

4. A nutrient medium for yeast which comprises a yeast assimilable carbohydrate material,

a yeast nutrient inorganic salt, and beta amino for stimulating activity of yeast u r 'i.

5. A method which comprises preparing a nutrient medium taining a yeast assimilable carbohydrate mam attached only to the beta position with respect to carboxyl, incorporating yeast with'said nutrient medium, and allowing the yeast to act 6. A for stimulating activity of yeast which comprises preparing a nutrient medium terial, a yeast nutrient inorganic salt, and'a'; nonocarboxylic organic acid having an amino containing a yeast assimilable carbohydrate material, a yeast nutrient inorganic salt, and beta alanine, incorporating yeast with' said nutrient medium, and allowing the yeast to act therein.

7. A method for stimulating activity of yeast 5 which comprises preparing a nutrient medium containing a yeast assimilable carbohydrate material, a yeast nutrient inorganic salt, beta alanine and aspartic acid, incorporating yeast with said nutrient medium, and allowing the yeast toact therein.

8. A method for stimulating growth of yeast which comprises preparing a nutrient medium containing a yeast assimilable carbohydrate material, a yeast nutrient inorganic salt, and a monocarboxylic organic acid having an amino group'attached only to the beta position with respect to carboxyl, seeding said nutrient medium with yeast, propagating the yeast therein,

and separating yeast from the medium.

a 9. A method for stimulating growth of yeast which comprises preparing a nutrient medium containing a yeast assimilable carbohydrate material, a yeast nutrient inorganic salt, and beta alanine, seeding said nutrient medium with yeast, propagating the yeast therein, and separating yeast from the medium.

10. A method for stimulating growth of yeast which comprises preparing a nutrient medium containing a yeast assimilable carbohydrate ma-' terial, a yeast nutrient inorganic salt, beta alanine and aspartic acid, seeding said nutrient medium with yeast, propagating the yeasttherein, and separating yeast from the .medium.

11. A method i'orthe production of bread which '5 comprises incorporating a monocarboxylic organic acid having an amino group attached on y to the beta position with respect to carbox'yl with flour, water, yeast, sugar, and other ingredients entering into the preparation of adough.

12. A method for the production of bread which comprises incorporating beta alanine with flour, water, yeast, sugar, and other ingredients entering into the preparation of a dough.

13. A method for the production of bread which comprises incorporating beta alanine and aspartic acid with flour, watei', yeast, sugar, and other ingredients entering into the preparation of a dough.

14. A nutrient medium for yeast which comprises a yeast assimilable material and a nionocarboxylic organic acid having nitrogen attached onlyto the beta poaition with respectto caracid. 

